Enligt Svenskt Vatten ska dagvattensystem vara dimensionerade för att klara ett regnmed en återkomsttid på 10 år. För att utvärdera om ett system är rätt dimensionerat kanen dagvattenmodell upprättas. Det är då viktigt att veta vilka nivåer ledningarna har mendenna information är bristfällig hos många kommuner. Ledningarna borde dock följatopografin i generella drag och borde därför kunna uppskattas därifrån.Syftet med denna studie var därför att utveckla en metod för hur vattenledningarnasnivåer kunde ansättas på ett enkelt sätt utifrån marknivån och hur stor betydelse detskulle ha vid dagvattenmodellering. Ett ytterligare syfte var att även bedöma Lidingöstads dagvattensystem, där information om ledningarnas nivåer saknades, utifrån dennametod. För att metoden skulle vara användbar var det också viktigt att den var enkel attapplicera även för stora dagvattensystem.Delar av Sundbybergs dagvattennät i Stockholms län användes för att utvecklametoden. Där var ledningarnas nivåer kända och en analys av detta resulterade i enmetod där brunnarnas djup, som styr ledningarnas nivåer, ansattes på 2 m djup. Ettundantag var tvunget att göras vid de fall då ledningarna fick bakfall. Där ansattes ettdjup så att ledningen låg horisontellt.Vid utvärdering av hur stor påverkan ansättningen av djupet hade togs hänsyn tillosäkerheten av avrinningskoefficienten genom att använda tre olika scenarier;oförändrad, 30 % lägre samt 30 % högre avrinningskoefficient. För varje brunn vägdesrisken för översvämning ihop från resultatet av dessa tre scenarier och sammanställdesmed att varje brunns trycknivå fick status över mark, under mark eller osäker. Dettagjordes för både modell med kända och med ansatta nivåer. Statusen för varje brunnjämfördes sedan dem emellan för att utvärdera hur bra metoden för att ansättabrunnarnas djup var.Resultatet av studien visar att metoden i stora drag gav samma resultat vad gäller riskenför översvämning jämfört med om nivåerna hade varit kända. Avvikelser uppstodfrämst vid diken men även för enstaka instängda områden och utlopp. För Lidingösdagvattennät hamnade trycknivån för 18 % av brunnarna över marknivån vid ett 10-årsregn och ytterligare 16 % var osäkra. / According to The Swedish Water and Wastewater Association (SWWA), a storm waternetwork must be able to handle a rainfall with a return period of 10 years. In order toevaluate whether a drain system is adequately dimensioned, a storm water model can beestablished. This requires knowledge about the levels at which the conduits are situated,and this information is insufficient in many areas. However, the pipes could largely beassumed to follow the topography and the pipes levels can be estimated from it.Therefore, the aim of this study was to develop a method for how the level of stormwater conduits could be assessed from the ground level, and the significance thismethod had for storm water modeling. A further aim was also to, according to thismethod; assess the storm water systems of the Lidingö community, which lackedinformation on the pipe levels. Furthermore, for the method to be useful it wasimportant to make it easily applicable even to large storm water networks.The method was developed using parts of the storm water network in Sundbyberg,Stockholm. The levels of the conduits were known beforehand, and an analysis of themresulted in a method where the depth of the manhole, which controls the levels of theconduits, was estimated to 2 m. An exception had to be made when the conduits were inreverse slope, in which cases horizontal slope was assumed.When evaluating the impact from the depth assessment on the runoff, the uncertaintyfrom the imperviousness was taken into account by using three different scenarios;unchanged, 30% lower and 30% higher imperviousness. The risk of flooding for eachone of the manholes was weighted from the results of these three scenarios. Thisresulted in a pressure level for each manhole, either above ground, below ground orinconclusive. This was done for the model with both known levels for the conduits, andwith the assessed levels. In order to evaluate how well the method for applying thedepth worked, the status of each manhole was compared between the two models.The conclusion from this study was that the method developed here, more or less gavethe same results as when the levels of the conduits were previously known.Discrepancies arose mainly in ditches, but also for a few landlocked areas and outlets.For the Lidingö storm water network, 18 % of the wells ended up with a pressure levelabove ground when applied to a rain with a 10 year return period. Another 16 % of thewells were inconclusive.

Researchers, explorers, and philosophers have dedicated many lifetimes attempting to discover, document, and quantify the vast physical processes and interactions occurring in nature. Our understanding of physical processes has often been reflected in the form of numerical models that assist academics in unraveling the many complexities that exist in our physical environment. To that end, integrated surface water-groundwater models attempt to simulate the complex processes and relationships occurring throughout the hydrologic cycle, accounting for evapotranspiration and surface water, variably saturated groundwater, and channel flows. <br /><br /> The Bass Lake watershed is located in the Muskoka district of Ontario, within a crystalline rock environment consistent with typical Canadian Shield settings. Numerous data collection programs and methods were used to compile environmental and field-scale datasets. The integrated surface water-groundwater model, HydroGeoSphere (Therrien et al. , 2005), was used for all Bass Lake watershed simulation models. <br /><br /> Simulation results were compared to expected trends and observed field data. The groundwater heads and flow vector fields show groundwater movement in expected directions with reasonable flow velocities. The subsurface saturation levels behave as expected, confirming the evapotranspiration component is withdrawing groundwater during plant transpiration. The surface water depths and locations of water accumulation are consistent with known and collected field data. The surface waters flow in expected directions at reasonable flow speeds. Simulated Bass Lake surface elevations were compared to observed surface water elevations. Low overland friction values produced the most accurate Bass Lake elevations, with high overland friction values slightly overestimating the Bass Lake water level throughout the simulation period. Fluid exchange between surface water and groundwater domains was consistent with expected flux rates. The integrated surface water-groundwater model HydroGeoSphere ultimately produced acceptable simulations of the Bass Lake model domain.

In recent decades, there has been increased global concern about observed climate change; however for future climatic impacts and anthropogenic forcings of climate change to be realistically predicted, natural climate variability in the past needs to be better understood. The aim of this research is to develop quantifiable proxy records of past climate change through the calibration of isotope values in modern surface waters and tree ring cellulose with meteorological and atmospheric records. Terrestrial proxy records that utilize oxygen and hydrogen isotope values to reconstruct paleoclimatic and paleohydrologic conditions are limited by a paucity of data on the modification of surface water isotope values prior to sequestration into proxy material. To address this gap in our knowledge and determine the most appropriate study sites, this research focuses on isotopic records preserved in surface water reservoirs, precipitation, and tree-ring cellulose. In the first study, δD, δ18O, and deuterium-excess values were determined for lakes and rivers from Tasmania, southeastern Australia. <p> The second focus of this research was to calibrate the δ18O, δD, and δ13C values of tree-ring cellulose from North America with instrumental records. A new high-resolution sampling procedure that uses a robotic micromilling device to very precisely map and sample along growth rings in trees is discussed. Additionally, a seasonally resolved (early/late wood) 110-year record of δ18O values from tree-ring α-cellulose from spruce species (<i>Picea mariana</i> and <i>P. glauca</i>) from east-central Saskatchewan, Canada is compared to growing season precipitation δ18O values, temperature, and relative humidity. The δ18O time series from α-cellulose display a high correlation with growing season precipitation isotope values (r = 0.86). δ18O α-cellulose time series from a white spruce (<i>Picea glauca</i>) also records seasonal changes in atmospheric circulation associated with the position of the circumpolar vortex and dominate modes of atmospheric variability such as the North Atlantic Oscillation and Pacific Decadal Oscillation.

Semi-arid regions, like the Okanagan Basin of British Columbia, Canada, are often faced with the difficulty of managing limited groundwater and surface water resources while accommodating rapid population growth and increasing land development. In the South Okanagan Basin, a better understanding of groundwater recharge sources, groundwater availability and susceptibility of water supplies to anthropogenic contamination is needed to best direct and protect the regions water resources. The purpose of this study was: (1) to characterize the regional hydrogeological setting of the South Okanagan Basin by establishing an isotopic and geochemical framework that included precipitation and surface waters of the Okanagan Basin and groundwaters of the South Okanagan Basin; and (2) to characterize nitrate contamination and its sources in shallow groundwaters of the Osoyoos area. Stable isotopes of water, nitrate and dissolved oxygen, groundwater chemistry, water levels and enriched tritium, tritium/helium and/or radiocarbon age dating techniques were used. Two provisional local meteoric water lines were established for the Okanagan Basin: &delta2H=6.06&delta18O31.21 (Osoyoos) and &delta2H=7.03&delta18O-12.68 (West Kelowna). Surface waters of the Okanagan River system were sources of irrigation water in the South Okanagan Basin valley and irrigation-return flow was the primary source of recharge for shallow groundwaters. Fractured bedrock in highlands east and west of the valley were not a significant source of recharge for shallow valley groundwater, however, may recharge deeper, or basal, valley deposits. As irrigation-return flow controls shallow groundwater dynamics in the valley sediments, groundwater quality is susceptible to anthropogenic contamination. In Osoyoos, nitrate was present in shallow groundwaters at concentrations of up to 24.4 mg/l N as a result of fertilizer nitrogen applied at the soil surface, mostly at orchards. Two agricultural drainage systems in north Osoyoos discharge roughly 1,900 kg N/year from nitrate-contaminated groundwater directly into Osoyoos Lake and may contribute in part to its eutrophication.

<p>Groundwater has an important role in forging the composition of surface water, supplying nutrients crucial for the development of balanced ecosystems and potentially introducing contaminants into otherwise pristine surface water. Due to water-rock interactions radium (Ra) in groundwater is typically much more abundant than in surface water. In saline environments Ra is soluble and is considered a conservative tracer (apart for radioactive decay) for Ra-rich groundwater seepage. Hence in coastal environments, where mostly fresh groundwater seep into saline surface water, Ra has been the prominent tracer for tracking and modeling groundwater seepage over more than three decades. However, due to its reactivity and non-conservative behavior, Ra is rarely used for tracing groundwater seepage into fresh or hypersaline surface water; in freshwater, Ra is lost mostly through adsorption onto sediments and suspended particles; in hypersaline environments Ra can be removed through co-precipitation, most notably with sulfate salts. </p><p>This work examines the use of Ra as a tracer for groundwater seepage into freshwater lakes and rivers and into hypersaline lakes. The study examines groundwater-surface water interactions in four different environments and salinity ranges that include (1) saline groundwater discharge into a fresh water lake (the Sea of Galilee, Israel); (2) modification of pore water transitioning from saline to freshwater along their flow through sediments (pore water in sediments underlying the Sea of Galilee, Israel); (3) fresh groundwater discharge into hypersaline lakes (Sand Hills, Nebraska); and (4) fresh groundwater discharge into a fresh water river (Neuse River, North Carolina). In addition to measurement of the four Ra isotopes (<super>226</super>Ra, <super>228</super>Ra, <super>223</super>Ra, <super>224</super>Ra), this study integrates geochemical (major and trace elements) with additional isotopic tools (strontium and boron isotopes) to better understand the geochemistry associated with the seepage process. To better understand the critical role of salinity on Ra adsorption, this study includes a series of adsorption experiments. The results of these experiments show that Ra loss through adsorption decreases with increasing salinity, and diminishes in salinity as low as ~5% of the salinity of seawater. </p><p>Integration of the geochemical data with mass-balance models corrected for adsorption allows estimating groundwater seepage into the Sea of Galilee (Israel) and the Neuse River (North Carolina). A study of the pore water underlying the Sea of Galilee shows significant modifications to the geochemistry and Ra activity of the saline pore water percolating through the sediments underlying the lake. In high salinity environments such as the saline lakes of the Nebraska Sand Hills, Ra is shown to be removed through co-precipitation with sulfate minerals, its integration into barite (BaSO₄) is shown to be limited by the ratio of Ra:Ba in the precipitating barite. </p><p>Overall, this work demonstrates that Ra is a sensitive tracer for quantifying groundwater discharge even in low-saline environments. Yet the high reactivity of Ra (adsorption, co-precipitation, production of the short-lived isotopes) requires a deep understanding of the geochemical processes that shape and control Ra abundances in water resources.</p> / Dissertation

Carters Creek in Brazos County, Texas, like many surface water reaches in the Texas Gulf Coast region, has been identified for bacteria and nutrient impairment on the Texas Commission on Environmental Quality (TCEQ) 303(d) List. Carters Creek drains a rapidly urbanizing watershed and has been found to carry high concentrations of dissolved organic carbon (DOC), nitrate, phosphate and sodium. These constituents have a severe impact on the creek?s capacity for healthy aquatic life and increase the potential for eutrophication downstream. The creek has also had chronic high Escherichia coli counts, making the creek unsuitable for contact recreation according to the accepted standard for surface water quality, which is a geometric mean of 126 CFU per 100 ml. In this study, grab samples were taken twice monthly from fifteen sites on Carters Creek and its subcatchments from July 2007 to June 2008. The samples were analyzed for E. coli, DOC, total N, NO3-N, NH4-N, Na+, K+, Mg2+, Ca2+, F-, Cl-, Br-, NO2-, SO42- and PO4-3. Mean annual DOC concentrations varied from 24.8 mg/L in Carter at Boonville Road to 55.5 mg/L in Wolfpen Creek; sodium varied from 33 mg/L in Carter at Old Reliance Road to 200 mg/L, also in Wolfpen Creek. Burton 4, the subcatchment with the highest geometric mean for E. coli with 2547 CFU/100 mL, was also sampled with greater geographical intensity for E. coli and optical brightener fluorescence at 445 nm to identify any leaking sewer pipes, but no evidence of defective pipes was found. During both the spring season and annual high flow (storm events), E. coli counts were positively correlated with total urban land use, probably caused by storm runoff carrying residues from impervious surfaces into the stream. High flow E. coli also had a negative relationship with potassium and a positive relationship with calcium, possibly suggesting a bioflocculation effect. Sites downstream of wastewater treatment plants (WWTPs) showed higher nitrate, phosphate, sodium, potassium, chloride and fluoride than other urban subcatchments. Creeks with golf courses carried more phosphate, sodium and fluoride than subcatchments without golf courses or WWTPs.

Concentrations of 17 organochlorine and 14 organophosphorus pesticides were measured in 27 ground and 11 surface water samples collected from a heavily agricultural area, Kumluca, in spring and fall seasons of 2005. The samples were preconcentrated by Solid Phase Extraction. GC-ECD and GC-NPD systems were used for quantitative determination of organochlorine and organophosphorus pesticides respectively. The quality check/quality assurance tests were performed by the analysis of field and laboratory blanks, standard reference materials, spiked control and sample matrices, surrogate standards, sampling and analysis replicates. It is observed that, sample matrix lowers average percent recoveries from 89% to 76%. The uncertainties of measurements were calculated to determine major factors affecting the analysis results. It was observed that uncertainty arising from extraction procedure was generally the highest. The most commonly observed pesticide was endosulfan (70%) and chlorpyriphos (53%) for organophosphorus and organochlorine pesticides. The highest average concentration was observed for heptachlor (26 ng/L) and fenamiphos (184 ng/L). Generally pesticides were detected more often in surface waters, where the concentrations were also higher. The concentrations of organophosphorus pesticides in spring, and organochlorine pesticides in fall season were higher. The high occurrences and detection of degradation products of chlorinated pesticides clearly indicate their intense use before 1980s. It is shown that, in Kumluca environment, degradation of these pesticides mostly occurs in surface waters. It is observed that agricultural activities affect water quality in the region. The total concentration limit (500ng/L) was exceeded for 27% of surface and 14% of ground water samples, at least once in both seasons. The legal limit for a single pesticide (100ng/L) was exceeded by 32 % of surface, 24 % of ground water samples.

Langmuir monolayers can be employed as simple model systems to study interactions at surfaces. Such investigations are important to fields ranging from biology to materials science. Herein, several aspects of these films and their associated water structure have been examined with vibrational sum frequency spectroscopy (VSFS). This second order nonlinear optical spectroscopy is particularly well suited for simultaneous investigations of the monolayer and the associated water structure with unprecedented surface specificity. The structures of these systems were altered through the control of experimental parameters including monolayer pressure, subphase temperature, pH and ionic content. Thermodynamic information about structural changes in a fatty amine monolayer's hydrophobic region was obtained by observation of the pressure and temperature dependence of the monolayer's solid to liquid phase transition. Further studies used the coordination of divalent cations to acid monolayers to perturb the water layers nearest to the film which enabled a better understanding of the water related VSFS features from these hydrophilic interfaces. Information from both the monolayer and water structure was then combined in order to examine the role of water in mediating ion-biomaterial interactions, often expressed in terms of the Hofmeister series.

<p>A road in operation along with its traffic can pose aserious pollutant threat to groundwater and surface water inits vicinity. Examples of pollutants are metals from thecorrosion of vehicles, rails and poles and the wear of roadsurfaces and tyres; hydrocarbons from the wear of roadsurfaces, tyres, exhausts, oils; sodium chloride from roadsalt; and hazardous goods discharged in accidents. Eventuallypollutants that are not degraded or retarded in soil will reachgroundwater and surface water. The chloride ion in deicing saltis a good tracer. It is conservative and highly soluble and notsubject to retardation or degradation. If the chlorideconcentration has increased in groundwater or surface water inthe vicinity of a deiced road, other road-related pollutantsmight also be present in the water.</p><p>Increased chloride concentrations have been observed inseveral water supplies, in groundwater as well as in surfacewater, since the 1970s. The number of affected water supplieshas also increased. The increase in chloride concentration inwaters is concurrent with the increase in deicing saltapplication and it is clear that most of the increase is due tothe application of deicing salt.</p><p>The thesis presents a simple tool that quantified theincrease in chloride concentration for water in a catchmentarea, based on a steady-state water balance. The data wereefficiently processed and presented as maps with GIS. At aregional catchment area scale, substantially increased chlorideconcentrations were calculated. The variation between catchmentareas was verified by a national monitoring programme of lakes.Deicing salt application was estimated to account for more thanhalf of the total chloride load for a catchment area in the midsouth of Sweden.</p><p>A distributed dynamic method was used to evaluate thetemporal and spatial variation of the chloride concentration inan aquifer. The distributed dynamic approach integrated thespreading of deicing salt from the road with the infiltrationin the unsaturated zone in the soil, which in turn wasintegrated with the groundwater flow. The simulation was runfor a 40-year period and showed a potential to describe aspecific system.</p><p><b>Keywords:</b>road, deicing salt, monitoring, chloride,catchment area, river basin, simulation, GIS, groundwater,surface water</p>

Under sommaren 2014 bröt den största skogsbranden ut i modern svensk historia. Branden startade i närheten av Sala och totalt brann cirka 14 000 ha. Till följd av klimatförändringar förväntas medeltemperaturen öka och nederbörden minska under sommarhalvåret i Sverige, vilket ökar risken för skogsbränder. Skogsbränder kan ha betydande effekter för akvatiska ekosystem och ett flertal studier av skogsbränders effekter har visat på förhöjda halter av näringsämnen, bas- och anjoner. Det branddrabbade området domineras av skogsmark, öppna torvmarker samt sjöar. Området har påverkats av ett intensivt skogsbruk och försurning. Med syfte att analysera brandens hårdhet och dess vattenkemiska effekter, utvärderades och klassificerades brandhårdheten. Analysen indikerade att ökad brandintensitet orsakat ökad brandhårdhet samt att skogsbeklädda dikade torvområden varit känsligare än öppna torvmarker. I området provtogs nio bäckar och tio sjöar. Under de första tre månaderna efter branden observerades höga halter av ammoniumkväve och sulfat i samtliga bäckar och i de flesta sjöarna inom det branddrabbade området. I Gärsjöbäcken var medianhalterna av ammoniumkväve 79 gånger högre efter branden. De höga ammoniumkvävehalterna medförde höga nitratkvävehalter till följd av nitrifikation. Surhet bedöms ofta genom pH och ANC (Acid neutralicing capacity) som är ett vattens förmåga att neutralisera en stark syra. Den initiala sulfatpulsen orsakade en sänkningav ANC i samtliga bäckar. Efter pulsen ökade ANC till följd av ökat läckage av kalium, kalcium och magnesium efter branden. Buffertkapaciteten varierade i bäckarna och i Myckelmossbäcken observerades högst sulfathalter och lägst ANC-värden. I april var ANC fortfarande lägre i Myckelmossbäcken än i övriga bäckar. Totalfosforhalterna ökade efter branden men inte i samma utsträckning som ammoniumkvävehalterna. Korrelationsanalyser gjordes mellan brandhårdhet och vattenkemiska parametrar. Maxhalterna av ammoniumkväve korrelerade positivt med svedd öppen torvmark och hårt brända kronor i skogsbeklädd torvmark. Det indikerade att när organiskt material förbränndes i öppna och skogsbeklädda torvmarker vid måttliga förbränningstemperaturer ökade läckaget av ammoniumkväve. / During the summer of 2014 the largest wildfire in Swedish modern history occurred. The fire was ignited in a forest close to the Swedish town Sala and incinerated a total of 14 000 ha. The frequency of wildfires is expected to increase, due to effects of climate change such as increased temperature and decreased precipitation during the summer months. Wildfires can have a considerable impact on aquatic ecosystems and previous studies of wildfires have shown elevated concentrations of nutrients, cat- and anions. The area of the fire mainly consists of forestland, peatland and lakes and has been affected by acidification and intensive forestry. To assess the fire severity and the effects on the water chemistry, the fire severity was analyzed and classified. The analysis indicated that increased fire intensity caused increased fire severity and that drained forested areas were more vulnerable to fire than undrained peatland. Measurements of water chemistry were conducted at nine streams and ten lakes inside the affected area. During the initial three months of the post-fire period large peaks of ammonium-nitrogen and sulphate were observed in the streams and in a majority of the lakes. In the stream Gärsjöbäcken the median concentrations of ammonium-nitrogen were 79 times higher after the fire. Due to nitrification the elevated concentrations of ammonium-nitrogen caused elevated concentrations of nitrate-nitrogen. ANC (Acid Neutralizing Capacity) and pH are often used to assess the acidity in surface waters, where ANC is the water’s ability to neutralize a strong acid. The initial peak of sulphate caused a drop in ANC but after the peak had past ANC increased due to elevated concentrations of base cations. The measured streams and lakes had different buffering capacity and in one stream Myckelmossbäcken the highest concentrations of sulphate and weakest buffering capacity were observed. In April ANC were still lower in Myckelmossbäcken than in other measured streams. Correlation analysis of fire severity and water chemistry indicated that the maximum concentrations of ammonium-nitrogen increased with severely burned canopies in drained forested peatlands and in scorched open peatland.